King Charles enjoyed a very special reunion on Wednesday after a day of engagements and audiences at Buckingham Palace.
According to the Court Circular, the monarch, 75, met with one of his distant royal relatives - Her Majesty Margareta, Custodian of the Romanian Crown, 74, and Prince Radu of Romania.
The Romanian and British royal families share a close relationship, and Margareta reportedly spent her childhood summer holidays with Charles and his sister Princess Anne.
The then Prince Charles also visited the family in Bucharest during an official tour in 2017 and attended King Michael I's funeral in December that year.
King Michael was the last King of Romania, reigning from July 1927 to June 1930 and again from September 1940 to his forced abdication in December 1947.
He met his wife Anne of Bourbon-Parma at the royal wedding and the pair married in Athens, Greece in 1948.
After King Michael's forced abdication, the couple raised their five daughters - Crown Princess Margareta, Princess Elena, Princess Irina, Princess Sophie and Princess Marie in Switzerland.
Margareta also attended boarding school in Hampshire in the UK in the 1960s and later studied at the University of Edinburgh in Scotland.
She enjoyed a long-term relationship with future British prime minister Gordon Brown while they were at university.
In 1994, she met art therapist and part-time actor, Radu Duda. The pair married in a civil wedding at Versoix two years later.
While Romania's royal family doesn't have an official role, Margareta formally assumed the role as Custodian of the Romanian Crown, following her father's death.
Margareta and Radu do not have any children so Margareta's younger sister, Princess Elena, is her heir.
An image shared by the Romanian royal family's Instagram account showed the couple before they boarded their flight to London.
Margareta looked elegant in a camel coat and matching trousers with a black rollneck and ballet flats, while her husband wrapped up warm in a double-breasted coat, jeans and a scarf.
Following the first day of the South Korean state visit and state banquet on Tuesday, King Charles presented honorary MBEs to K-pop band Blackpink at Buckingham Palace in the presence of President Yoon Suk Yeol and First Lady Kim Keon Hee.
The special investiture on Wednesday morning for Jennie Kim, Jisoo Kim, Lisa Manobal and Rose Park from South Korea's biggest girl group was in recognition of the band's role as advocates for the Cop26 Summit in Glasgow.
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